阅读说明：本技术 一种降低本底噪音装置及其方法 (Device and method for reducing background noise ) 是由 陈科 刘朝亮 张咏 丁祖庚 杨龙 于 2020-06-09 设计创作，主要内容包括：本发明公开了一种降低本底噪音装置及其方法,通过将音频卡农头引出的三组所述信号线分别与每一所述第一电容器对应并联,进行电容耦合,用以降低前级设备带来的本底噪音；然后利用至少十厘米长度的所述屏蔽组件沿所述信号线长度方向包覆三组所述信号线,用以屏蔽空气中的高频,降低设备本底噪音,之后,三组所述信号线远离所述屏蔽组件的一端分别与每一所述电感器对应串联,进行电感耦合,用以屏蔽阻隔前级电路剩余的本底噪音；三个所述电感器远离所述屏蔽组件一侧的三个第二电容器分别与三组信号线对应并联,用以在进入信号处理前进行二次电容耦合,前级电路剩余的本底噪音进行二次降噪。以此能够良好的抑制设备底噪,提升用户体验感。(The invention discloses a device and a method for reducing background noise.A three groups of signal wires led out from an audio card head are respectively connected with each first capacitor in parallel correspondingly for capacitive coupling so as to reduce the background noise brought by preceding-stage equipment; then, covering three groups of signal wires by using the shielding assembly with the length of at least ten centimeters along the length direction of the signal wires for shielding high frequency in the air and reducing the background noise of equipment, and then, respectively connecting one ends of the three groups of signal wires, which are far away from the shielding assembly, in series with each inductor correspondingly for inductive coupling so as to shield and block the residual background noise of a preceding stage circuit; and three second capacitors at one side of the three inductors, which is far away from the shielding component, are respectively connected with the three groups of signal lines in parallel correspondingly and are used for carrying out secondary capacitive coupling before entering signal processing, and carrying out secondary noise reduction on residual background noise of a preceding stage circuit. Therefore, the device background noise can be well inhibited, and the user experience is improved.)

1. The utility model provides a reduce background noise device, its characterized in that, including audio frequency card agricultural head structure, with capacitor assembly, shielding subassembly, the circuit board subassembly that audio frequency card agricultural head structure connects, audio frequency card agricultural head structure includes joint and signal line group, capacitor assembly with signal line group connects in parallel, three groups of shielding subassembly cladding signal line is located capacitor assembly keeps away from one side of joint, the circuit board subassembly with signal line group connects.

2. The noise floor reduction device according to claim 1, wherein the capacitor assembly includes three first capacitors, and the signal line group includes three groups of signal lines, and each of the first capacitors is connected in parallel with each of the groups of signal lines.

3. The noise floor reduction device of claim 2, wherein the shield assembly has a dimension along the length of the signal line of no less than ten centimeters.

4. The noise floor reduction device of claim 3, wherein the circuit board assembly comprises an inductor, the inductor being connected in series with the signal line group.

5. The noise floor reduction device according to claim 4, wherein the number of the inductors is three, and each of the inductors is respectively connected in series with each of the groups of the signal lines.

6. The noise floor reduction device of claim 4, wherein the capacitive component further comprises a second capacitor connected in parallel with the set of signal lines and located on a side of the shielding component away from the first capacitor.

7. The noise floor reduction device according to claim 6, wherein the number of the second capacitors is three, and each of the second capacitors is connected in parallel with each of the signal lines and is located on a side of the inductor away from the shielding assembly.

8. The method of claim 7, wherein the step of reducing the background noise comprises the steps of;

s1, leading out the signal line group from the connector, connecting the signal line group and the capacitor assembly in parallel, and performing capacitive coupling to reduce the background noise brought by the preceding stage equipment;

s2, the shielding component covers the signal line group along the length direction of the signal line to shield high frequency in the air and reduce the background noise of the equipment;

s3, connecting the end of the signal line group far away from the shielding component with the circuit board component in series correspondingly, and performing inductive coupling to shield and block the residual background noise of the preceding stage circuit;

s4, the capacitance component is used again to connect with the signal line group in parallel, so as to carry out secondary capacitance coupling before entering signal processing, and secondary noise reduction is carried out on the residual background noise of the preceding stage circuit.

9. The method of reducing noise floor device of claim 8,

in step S2: the shielding assembly with the length of at least ten centimeters covers three groups of signal wires along the length direction of the signal wires;

in step S3: and three groups of ends of the signal wires, which are far away from the shielding component, are respectively connected with each inductor in series correspondingly.

10. The method of reducing noise floor of claim 9,

in step S4: and three second capacitors at one side of the three inductors, which is far away from the shielding component, are respectively connected with the three groups of signal lines in parallel.

Technical Field

The invention relates to the technical field of digital audio wireless transceiving devices, in particular to a device and a method for reducing background noise.

Background

At present, digital audio wireless transceiver equipment is widely used in professional stage audio wireless transmission scenes, and the scene of the professional stage has higher requirements on sound quality and audio bandwidth.

A common approach for digital audio wireless transceiving equipment in the market is that in a standard application system, sound is finally presented to listeners through a microphone, a transmitter, an air interface, a receiver, an audio mixer, a power amplifier and a loudspeaker. The equipment adopts a standard card and nong interface, and the circuit is a standard audio shielding line.

However, when the digital audio wireless transceiver device is compared with the original wired transmission transceiver device, the sound played by the digital audio wireless transceiver device has obvious device noise (device noise for short), which affects the user experience.

Disclosure of Invention

The invention aims to provide a device and a method for reducing background noise, and aims to solve the technical problem that in the prior art, the sound played by digital audio wireless transceiver equipment has obvious equipment noise and influences user experience.

In order to achieve the purpose, the device for reducing the background noise comprises an audio frequency agricultural clamping head structure, a capacitor assembly, a shielding assembly and a circuit board assembly, wherein the capacitor assembly, the shielding assembly and the circuit board assembly are connected with the audio frequency agricultural clamping head structure, the audio frequency agricultural clamping head structure comprises a connector and a signal wire set, the capacitor assembly is connected with the signal wire set in parallel, the shielding assembly covers three groups of signal wires and is positioned on one side, away from the connector, of the capacitor assembly, and the circuit board assembly is connected with the signal wire set.

The capacitance component comprises three first capacitors, the signal line group comprises three groups of signal lines, and each first capacitor is correspondingly connected with each group of signal lines in parallel.

Wherein the dimension of the shielding component along the length direction of the signal wire is not less than ten centimeters.

Wherein the circuit board assembly includes an inductor in series with the signal line group.

The number of the inductors is three, and each inductor is respectively connected with each group of the signal lines in series correspondingly.

The capacitance component further comprises a second capacitor, and the second capacitor is connected in parallel with the signal line group and is positioned on one side, far away from the first capacitor, of the shielding component.

The number of the second capacitors is three, and each second capacitor is respectively connected with each group of the signal lines in parallel and is positioned on one side of the inductor, which is far away from the shielding component.

The invention also provides a method for reducing background noise, which comprises the following steps;

s1, leading out the signal line group from the connector, connecting the signal line group and the capacitor assembly in parallel, and performing capacitive coupling to reduce the background noise brought by the preceding stage equipment;

s2, the shielding component covers the signal line group along the length direction of the signal line to shield high frequency in the air and reduce the background noise of the equipment;

s3, connecting the end of the signal line group far away from the shielding component with the circuit board component in series correspondingly, and performing inductive coupling to shield and block the residual background noise of the preceding stage circuit;

s4, the capacitance component is used again to connect with the signal line group in parallel, so as to carry out secondary capacitance coupling before entering signal processing, and secondary noise reduction is carried out on the residual background noise of the preceding stage circuit.

Wherein, in step S2: the shielding assembly with the length of at least ten centimeters covers three groups of signal wires along the length direction of the signal wires;

in step S3: and three groups of ends of the signal wires, which are far away from the shielding component, are respectively connected with each inductor in series correspondingly.

Wherein, in step S4: and three second capacitors at one side of the three inductors, which is far away from the shielding component, are respectively connected with the three groups of signal lines in parallel.

The invention relates to a device and a method for reducing background noise.A three groups of signal wires led out from an audio frequency card farm head are respectively connected with each first capacitor in parallel correspondingly for capacitive coupling so as to reduce the background noise brought by preceding-stage equipment; then, covering three groups of signal wires by using the shielding assembly with the length of at least ten centimeters along the length direction of the signal wires for shielding high frequency in the air and reducing the background noise of equipment, and then, respectively connecting one ends of the three groups of signal wires, which are far away from the shielding assembly, in series with each inductor correspondingly for inductive coupling so as to shield and block the residual background noise of a preceding stage circuit; and three second capacitors at one side of the three inductors, which is far away from the shielding component, are respectively connected with the three groups of signal lines in parallel correspondingly and are used for carrying out secondary capacitive coupling before entering signal processing, and carrying out secondary noise reduction on residual background noise of a preceding stage circuit. Therefore, the device background noise can be well inhibited, and the user experience is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a flow chart of the structure of the device for reducing background noise of the present invention.

Fig. 2 is a graph of noise reduction versus length of a shielded wire in accordance with the present invention.

FIG. 3 is a flow chart of a method for reducing background noise according to the present invention.

The audio card comprises a 1-audio card head structure, 11-connectors, 12-signal line groups, 121-signal lines, 2-capacitance components, 21-first capacitors, 22-second capacitors, 3-shielding components, 4-circuit board components and 41-inductors.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention. Further, in the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

Referring to fig. 1 and 2, the present invention provides a technical solution:

the utility model provides a reduce background noise device, including audio frequency card agricultural head structure 1, with electric capacity subassembly 2, shielding component 3, the circuit board subassembly 4 that audio frequency card agricultural head structure 1 connects, audio frequency card agricultural head structure 1 is including connecting 11 and signal line group 12, electric capacity subassembly 2 with signal line group 12 is parallelly connected, 3 cladding three groups of shielding component signal line 121 is located electric capacity subassembly 2 is kept away from connect one side of 11, circuit board subassembly 4 with signal line group 12 is connected.

The capacitance component 2 includes three first capacitors 21, the signal line group 12 includes three groups of signal lines 121, and each first capacitor 21 is connected in parallel with each group of signal lines 121.

The dimension of the shielding assembly 3 along the length direction of the signal line 121 is not less than ten centimeters.

The circuit board assembly 4 includes an inductor 41, and the inductor 41 is connected in series with the signal line group 12.

The number of the inductors 41 is three, and each inductor 41 is respectively connected in series with each group of the signal lines 121.

The capacitive component 2 further comprises a second capacitor 22, the second capacitor 22 being connected in parallel with the signal line group 12 and being located on a side of the shielding component 3 remote from the first capacitor 21.

The number of the second capacitors 22 is three, and each second capacitor 22 is connected in parallel with each group of the signal lines 121, and is located on a side of the inductor 41 away from the shielding component 3.

In the present embodiment: the background noise reducing device is arranged at the front end of an original signal input circuit of the transmitting end; the background noise reducing device can be divided into the following four parts:

a first part: the three first capacitors 21 and the three second capacitors 22 are all ceramic capacitors, and after three groups of signal lines 121 are led out from the connector 11, because each first capacitor 21 is correspondingly connected in parallel with each group of signal lines 121, capacitive coupling is performed immediately through the three first capacitors 21, so that background noise caused by preceding-stage equipment is reduced, wherein the values of the first capacitors 21 are influenced by the following conditions:

capacitive reactance formula: x_C=1/(2 π fC) wherein X_CIs capacitive reactance, C is capacitance (F), F is the operating frequency (Hz) of the device, theoretically, X_CThe smaller the value, the better, i.e., the larger the C value, the better.

The size of the space for the circuit design will limit the type of said first capacitor 21, which is the final determined capacitance type of 0402# capacitor, taking the device to which the invention is directed as an example.

The usage scenario of the device will limit the material of the first capacitor 21, and taking the device of the present invention as an example, the finally determined capacitance material is NPO capacitance.

According to the conditions, in the equipment scene aimed by the invention, the capacitors of 220pF, 0402# and NPO are selected, so that the minimum capacitive reactance X which can be obtained in engineering design and product mass production is obtained_C。

The second part is the three groups of signal wires 121 from the audio frequency chip structure 1 to the circuit board, and the second part needs to be shielded by using the shielding component 3; repeated experiments verify that the length of the shielding component 3 is at least ten centimeters for the invention by adopting the Faraday principle for shielding and having requirements on the length of the shielding component 3. Since this part connects the signal line 121 between the audio cartridge head structure 1 and the circuit board, it belongs to a physical entity that must be present. High frequencies in the air (air) are easily sensed, and the principle of the antenna is similar to that of an antenna, so that shielding is needed to avoid interference. In addition, it is found through experiments that the length of the signal line 121 is increased after the signal line is shielded, so that the background noise of the device can be reduced. According to the experimental result, the relation between the noise reduction effect and the length of the generated noise signal which is attenuated due to the distance in the partial transmission is analyzed according to the principle, the following curve (as shown in fig. 2) is obtained through experiments, and the effect of inhibiting the equipment bottom noise by the shielding wire with the length of ten centimeters in the whole technical scheme is better value required by the cost, the effect and the accessory installation space; but it is noteworthy that: the noise reduction value in the curve is based on the corresponding equipment of the invention, and after the scheme of the invention is integrally realized, the corresponding measured value and the independent design of the part can not bring the obvious noise reduction effect.

And a third part, each inductor 41 is respectively connected in series with each group of the signal lines 121. The part of the design is arranged on a circuit board, signals pass through the signal wire 121 covered by the shielding component 3, after entering the circuit board and before entering signal processing, inductive coupling is carried out immediately, the residual background noise of a preceding stage circuit is shielded and blocked, and the value of the inductor 41 is influenced by the following conditions:

inductance formula: x_L=2 pi fL wherein X_LIs an inductive reactance, L is an inductance (H), and f is an operating frequency (Hz) of the device. Theoretically, X_LThe larger the L value, the better; the use scenario of the device will limit the material of the inductor L, and with the device to which the present invention is directed, magnetic beads are finally used.

According to the above conditions, in the device scene aimed at by the invention, we select 0402#, impedance 2700 Ω (@ 1 GHz) BLM18HE152SN1 magnetic beads, thereby obtaining the maximum inductive reactance X that can be obtained in engineering design and product mass production_L。

The fourth part: each of the second capacitors 22 is connected in parallel with each of the signal lines 121, and is located on a side of the inductor 41 away from the shielding component 3. The part is designed and arranged on a circuit board, signals enter the circuit board through the signal wire 121 covered by the shielding component 3 and then are subjected to secondary capacitive coupling before entering the signal processing, and secondary noise reduction is performed on residual background noise of a preceding stage circuit. The principle and the capacitance parameter value mode of the part are the same as the conception of the second part of the circuit.

The first part and the second part are realized on the signal line 121 between the audio truck head structure 1 and the circuit board, and the third part and the fourth part are realized on the circuit board and are the previous stage circuit parts of signal processing. The four parts of circuit design are relatively independent for the whole equipment function, and can be applied to other circuits related to wireless signal transmission.

A large number of tests verify that the four-part circuit design forms an integral scheme, the equipment bottom noise can be well inhibited, and the effect can be reduced by more than 20 dB. The four parts of the invention have a combined effect on the noise reduction effect, and if any part is lacked, the noise reduction effect is greatly reduced. Through the device for reducing the background noise can well inhibit the equipment background noise and improve the user experience.

Referring to fig. 3, the present invention further provides a method for reducing background noise, comprising the following steps;

s1, leading out the signal line group 12 from the connector 11, connecting the signal line group 12 and the capacitor assembly 2 in parallel for capacitive coupling, so as to reduce the background noise brought by the preceding stage equipment;

s2 the shielding component 3 with the length of at least ten centimeters covers three groups of signal wires 121 along the length direction of the signal wires 121, so as to shield high frequency in the air and reduce the background noise of the equipment;

s3, the ends of the three groups of signal lines 121 far from the shielding assembly 3 are respectively connected in series with each of the inductors 41, and are inductively coupled to shield and block the residual background noise of the previous stage circuit;

s4 three second capacitors 22 on the side of the inductor 41 away from the shielding assembly 3 are respectively connected in parallel with the three sets of signal lines 121 for performing secondary capacitive coupling before signal processing, and performing secondary noise reduction on the residual background noise of the previous stage circuit.

Three groups of signal wires 121 led out from the audio truck head are respectively connected with each first capacitor 21 in parallel correspondingly to carry out capacitive coupling so as to reduce background noise brought by preceding-stage equipment; then, at least ten centimeters of shielding assemblies 3 are used for covering three groups of signal wires 121 along the length direction of the signal wires 121 to shield high frequency in the air and reduce the background noise of the equipment, and then, one ends of the three groups of signal wires 121 far away from the shielding assemblies 3 are respectively connected with each inductor 41 in series correspondingly to perform inductive coupling to shield and block the residual background noise of the front-stage circuit; three second capacitors 22 on the side of the inductor 41 far away from the shielding assembly 3 are respectively connected in parallel with the three groups of signal lines 121 correspondingly, so as to perform secondary capacitive coupling before entering signal processing, and perform secondary noise reduction on the residual background noise of the preceding stage circuit, thereby well inhibiting the equipment background noise and improving the user experience.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.